public static DateTime GetNextDate(this RecurringTransaction model, out bool isValid)
{
var date = model.StartDate;
isValid = true;
switch (model.Type)
{
case RecurringType.Once:
case RecurringType.Daily:
{
// the start date is the current date
break;
}
case RecurringType.SemiMonthly:
case RecurringType.Monthly:
{
// the start date is the minimum date to start
var seed = date.FirstOfMonth();
var day = (int)model.DayOfMonth;
var desiredDate = DateTime.MinValue;
do
{
desiredDate = DateMath.GetDate(day, seed);
seed = seed.AddMonths(1);
} while (model.StartDate > desiredDate);
date = desiredDate;
break;
}
case RecurringType.Weekly:
{
// the start date is the minimum date to start
if (model.Days != RecurringDayOfWeek.None)
{
while (!model.Days.Contains(date.DayOfWeek))
{
date = date.AddDays(1);
}
}
else
{
isValid = false;
}
break;
}
}
return(date);
}
public static IEnumerable <DateTime> GenerateDates(this RecurringTransaction model, DateTime date, DateTime max)
{
var isDay1 = true;
var week = new Queue <DateTime>(DateMath.GetWeek(date));
week.Dequeue();
var dateCount = 0;
while (date < max)
{
if (model.EndType == RecurringEndType.ByDate && date.Date >= model.EndDate)
{
break;
}
yield return(date.Date);
++dateCount;
if (model.Type == RecurringType.Once)
{
// that's it
break;
}
if (model.EndType == RecurringEndType.ByCount && dateCount >= model.MaxOccurrences)
{
break;
}
switch (model.Type)
{
case RecurringType.Daily:
{
date = date.AddDays(model.Period);
break;
}
case RecurringType.Monthly:
{
var seed = date.AddMonths(model.Period);
date = DateMath.GetDate((int)model.DayOfMonth, seed);
break;
}
case RecurringType.SemiMonthly:
{
if (isDay1)
{
// the current date is day1, so get day2
date = DateMath.GetDate((int)model.DayOfMonth2, date);
isDay1 = false;
}
else
{
// get day1 again
var seed = date.AddMonths(model.Period);
date = DateMath.GetDate((int)model.DayOfMonth, seed);
isDay1 = true;
}
break;
}
case RecurringType.Weekly:
{
while (week.Count > 0)
{
date = week.Dequeue();
if (model.Days.Contains(date.DayOfWeek))
{
break;
}
}
if (week.Count == 0 && !model.Days.Contains(date.DayOfWeek))
{
// we've gone through the week; no more dates left
// so start over again at next week
date = date.AddDays(-6).AddDays(7 * model.Period);
while (!model.Days.Contains(date.DayOfWeek))
{
date = date.AddDays(1);
}
week = new Queue <DateTime>(DateMath.GetWeek(date));
week.Dequeue();
}
break;
}
}
}
}